Incredibly Rare Baby Dinosaur Skeleton Found In Canada

The tiny,
intact skeleton of a baby rhinoceroslike dinosaur has been
unearthed in Canada.

The toddler was just 3 years old and 5 feet (1.5 meters) long
when it wandered into a river near Alberta, Canada, and drowned
about 70 million years ago. The beast was so well-preserved that
some of its skin left impressions in the nearby rock.

"The big ones just preserve better: They don't get eaten, they
don't get destroyed by animals," said study co-author Philip
Currie, a paleobiologist at the University of Alberta. "You
always hope you're going to find something small and that it will
turn out to be a dinosaur."

Paleontologists had unearthed a few individual bones from smaller
ceratopsids in the past. But without intact juvenile skeletons,
such bones aren't very useful, as scientists don't really know
how each bone changes during each stage of the animals' lives,
Currie said.

The team was bone-hunting in Dinosaur Provincial Park in Alberta
when Currie came upon what looked like a turtle shell sticking
out from a hillside. Upon closer inspection, the fossil turned
out to be a frill, the bony decorative headgear that surrounds the
back of the head in ceratopsids.

When the team excavated, they found the fossilized skeleton of a
tiny dinosaur they identified as a Chasmosaurus belli, a
species commonly found in the area.

Drowning victim

Amazingly, almost the entire skeleton was intact, although
sometime in the past, a sinkhole had opened up below the beast
and the forelimbs had fallen away into an abyss. The fossil was
so well-preserved that the tiny, rosettelike pattern on its skin was imprinted in the rock
below the dinosaur.

Based on its size, the team estimates the dinosaur was about 3
years old — just out of infancy — when it perished. (Like humans,
these dinosaurs typically take about 20 years to reach maturity,
at which point they have 6.5-foot-long [2 meters] skulls and
weigh 3 to 4 tons.)

The fossil was found in sediments associated with watery
environments and didn't have any bite marks or trace of injury,
so it's likely the dino toddler likely drowned.

"I think it may have just gotten trapped out of its league in
terms of water current," Currie told LiveScience.

Soon after, the baby dinosaur was buried by sediments and left
untouched for millions of years.

Growth rates

Aside from being cute, the new fossil helps paleontologists
understand how these plant-eating dinosaurs grew. Paleontologists
can then better identify and age the myriad individual bones from
juveniles discovered over the years.

Already, the team has learned that Chasmosaur juvenile
frills look different from those on adults, and that limb
proportions don't change much as they grow. Predatory theropods
such as Tyrannosaurus rex have
disproportionately long limbs as juveniles, presumably to keep up
with the adults in the pack.

By contrast, "in Chasmosaurians, the proportions are
essentially the same, which probably means the adults were
probably never moving that fast," Currie said. "There was never
priority for these animals to run to keep up with the adults."